<!doctype html>
<html lang="en">
<head>
	<meta charset="UTF-8">
	<title>js示例4-4-3</title>
	<script>
		var string1 = "This is a 'car'.", string2 = 'That is a "boat". \n';
		var string3 = "This is a 'student'.";
		var string4 = "She is " + 18;
		alert(string1 + string2 + string3 + string4);
	</script>
</head>
<body>
	
</body>
</html>